Better performance on low-end PC?

Is there any way I can get better performance on GW2? My computer is in the shop and I'm current using my old low-end PC and with everything set on the lowest possible and even the resolution, it's still a bit slow with the frames. Is there any way to get the most out of the game. I don't care about the quality. I just need a performance boost.

A really minor thing you can do is ending Explorer.exe when you don't need it. You can open up task manger (ctrl alt delete), end the process, and reopen it when you need to. It's really a minimal boost, but it's something.